package twist

import (
	"context"
	"fmt"
	"net/http"
	"regexp"
	"strings"

	"github.com/trufflesecurity/trufflehog/v3/pkg/common"
	"github.com/trufflesecurity/trufflehog/v3/pkg/detectors"
	"github.com/trufflesecurity/trufflehog/v3/pkg/pb/detectorspb"
)

type Scanner struct{}

// Ensure the Scanner satisfies the interface at compile time
var _ detectors.Detector = (*Scanner)(nil)

var (
	client = common.SaneHttpClient()

	// Make sure that your group is surrounded in boundary characters such as below to reduce false positives
	accessToken = regexp.MustCompile(detectors.PrefixRegex([]string{"twist"}) + `\b(?:oauth2:)?([0-9a-f]{40})\b`)
)

// Keywords are used for efficiently pre-filtering chunks.
// Use identifiers in the secret preferably, or the provider name.
func (s Scanner) Keywords() []string {
	return []string{"twist"}
}

// FromData will find and optionally verify Twist secrets in a given set of bytes.
func (s Scanner) FromData(ctx context.Context, verify bool, data []byte) (results []detectors.Result, err error) {
	dataStr := string(data)

	matches := accessToken.FindAllStringSubmatch(dataStr, -1)

	for _, match := range matches {
		if len(match) != 2 {
			continue
		}
		resMatch := strings.TrimSpace(match[1])
		setAuth := resMatch

		if strings.Contains(match[0], "oauth") {
			setAuth = fmt.Sprintf("oauth2:%s", strings.TrimSpace(match[1]))
		}

		s1 := detectors.Result{
			DetectorType: detectorspb.DetectorType_Twist,
			Raw:          []byte(resMatch),
		}

		if verify {
			req, err := http.NewRequestWithContext(ctx, "GET", "https://api.twist.com/api/v3/users/get_session_user", nil)
			if err != nil {
				continue
			}
			req.Header.Add("Authorization", fmt.Sprintf("Bearer %s", setAuth))
			res, err := client.Do(req)
			if err == nil {
				defer res.Body.Close()
				if res.StatusCode >= 200 && res.StatusCode < 300 {
					s1.Verified = true
				} else {
					// This function will check false positives for common test words, but also it will make sure the key appears 'random' enough to be a real key
					if detectors.IsKnownFalsePositive(resMatch, detectors.DefaultFalsePositives, true) {
						continue
					}
				}
			}
		}
		results = append(results, s1)
	}
	return results, nil
}

func (s Scanner) Type() detectorspb.DetectorType {
	return detectorspb.DetectorType_Twist
}
